Beneficial effects of intra-arterial reserpine after upper-extremity embolectomy: a prospective randomised trial

Comparative effects of nitric oxide dependent and independent vasodilation on impaired hindlimb revascularization in eNOS−/− mice

Ischemia due to vascular occlusion induces vasodilation as an initial response, followed by arteriogenesis or angiogenesis. Vasodilation through nitric oxide (NO) independent and dependent mechanisms may be sufficient to restore the altered neovascularization in pathological situations where the NO is altered. Using a posterior limb claudication model to evaluate ischemia-induced revascularization in eNOS−/− mice, we compared the effects of sodium nitrite, a NO-dependent vasodilator, and prazocin, an alpha-adrenergic blocker and NO-independent vasodilator, on hindlimb revascularization. We evaluated the blood flow of the hindlimbs, NO and nitrites metabolites, the expression of tissue endothelial cell markers and proangiogenic factors, as well as the gait locomotion. Our results suggest that the use of a peripheral vasodilator can substitute the initial absence of NO as an endogenous vasodilator. However, final resolution of the ischemic process requires a NO-mediated pathway, which through changes in vascular hemodynamics, promotes the generation of angiogenic messengers facilitating the functional recovery of the damaged limb.

Thrombolysis for acute upper extremity deep vein thrombosis

BACKGROUND

About 5% to 10% of all deep vein thromboses occur in the upper extremities. Serious complications of upper extremity deep vein thrombosis, such as post-thrombotic syndrome and pulmonary embolism, may in theory be avoided using thrombolysis. No systematic review has assessed the effects of thrombolysis for the treatment of individuals with acute upper extremity deep vein thrombosis.

OBJECTIVES

To assess the beneficial and harmful effects of thrombolysis for the treatment of individuals with acute upper extremity deep vein thrombosis.

SEARCH METHODS

The Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (29 March 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2), and three trial registries (World Health Organization International Clinical Trials Registry, ClinicalTrials.gov, and ISRCTN registry) for ongoing and unpublished studies. We additionally searched the registries of the European Medical Agency and the US Food and Drug Administration (December 2016).

SELECTION CRITERIA

We planned to include randomised clinical trials irrespective of publication type, publication date and language that investigated the effects of thrombolytics added to anticoagulation, thrombolysis versus anticoagulation, or thrombolysis versus any other type of medical intervention for the treatment of acute upper extremity deep vein thrombosis.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all records to identify those that met inclusion criteria. We planned to use the standard methodological procedures expected by Cochrane. We planned to use trial domains to assess the risks of systematic error (bias) in the trials. We planned to conduct trial sequential analyses to control for the risk of random errors and to assess the robustness of our conclusions. We planned to consider a P value of 0.025 or less as statistically significant. We planned to assess the quality of the evidence using the GRADE approach. Our primary outcomes were severe bleeding, pulmonary embolism, and all-cause mortality.

MAIN RESULTS

We found no trials eligible for inclusion. We also identified no ongoing trials.

AUTHORS' CONCLUSIONS

There is currently insufficient evidence from which to draw conclusion on the benefits or harms of thrombolysis for the treatment of individuals with acute upper extremity deep vein thrombosis as an add-on therapy to anticoagulation, alone compared with anticoagulation, or alone compared with any other type of medical intervention. Large randomised clinical trials with a low risk of bias are warranted. They should focus on clinical outcomes and not solely on surrogate measures.